/// <summary>
/// Performs a deep copy of an existing deserializer state into another serializer state.
/// This implementation does not analyze the source object graph and therefore cannot detect multiple references to the same object.
/// Such cases will result in object duplication.
/// </summary>
/// <param name="from">source state</param>
/// <param name="to">target state</param>
/// <exception cref="ArgumentNullException"><paramref name="to"/> is null.</exception>
/// <exception cref="InvalidOperationException">Target state was already set to a different object type than the source state.</exception>
/// <exception cref="DeserializationException">Security violation due to amplification attack or stack overflow DoS attack,
/// or illegal pointer detected during deserialization.</exception>
public static void DeepCopy(DeserializerState from, SerializerState to)
{
if (to == null)
{
throw new ArgumentNullException(nameof(to));
}
if (from.Caps != null && to.Caps != null)
{
to.Caps.Clear();
to.Caps.AddRange(from.Caps);
}
var ds = to.Rewrap <DynamicSerializerState>();
IReadOnlyList <DeserializerState> items;
switch (from.Kind)
{
case ObjectKind.Struct:
ds.SetStruct(from.StructDataCount, from.StructPtrCount);
ds.Allocate();
from.StructDataSection.CopyTo(ds.StructDataSection);
for (int i = 0; i < from.StructPtrCount; i++)
{
DeepCopy(from.StructReadPointer(i), ds.BuildPointer(i));
}
break;
case ObjectKind.ListOfBits:
ds.SetListOfValues(1, from.ListElementCount);
from.RawData.CopyTo(ds.RawData);
break;
case ObjectKind.ListOfBytes:
ds.SetListOfValues(8, from.ListElementCount);
from.RawData.CopyTo(ds.RawData);
break;
case ObjectKind.ListOfEmpty:
ds.SetListOfValues(0, from.ListElementCount);
break;
case ObjectKind.ListOfInts:
ds.SetListOfValues(32, from.ListElementCount);
from.RawData.CopyTo(ds.RawData);
break;
case ObjectKind.ListOfLongs:
ds.SetListOfValues(64, from.ListElementCount);
from.RawData.CopyTo(ds.RawData);
break;
case ObjectKind.ListOfShorts:
ds.SetListOfValues(16, from.ListElementCount);
from.RawData.CopyTo(ds.RawData);
break;
case ObjectKind.ListOfPointers:
ds.SetListOfPointers(from.ListElementCount);
items = (IReadOnlyList <DeserializerState>)from.RequireList();
for (int i = 0; i < from.ListElementCount; i++)
{
DeepCopy(items[i], ds.BuildPointer(i));
}
break;
case ObjectKind.ListOfStructs:
ds.SetListOfStructs(from.ListElementCount, from.StructDataCount, from.StructPtrCount);
items = (IReadOnlyList <DeserializerState>)from.RequireList();
for (int i = 0; i < from.ListElementCount; i++)
{
DeepCopy(items[i], ds.ListBuildStruct(i));
}
break;
case ObjectKind.Capability:
ds.SetCapability(from.CapabilityIndex);
break;
}
to.InheritFrom(ds);
}
